Arming device for a submersible explosive weapon

ABSTRACT

An underwater arming device responsive to water pressure comprises a rotating body including a printed circuit for electrically actuating a detonator after a predetermined degree of rotation. A latch prevents rotation until water pressure exceeds a predetermined value. Rotation speed is controlled by a set of discs engaging a viscous medium.

Jan. 1, 1974 ARMING DEVICE FOR A SUBMERSIBLE EXPLOSIVE WEAPON Jan Bjork, Malmo, Sweden Svenska Aktiebolaget Bromsregulator, Malmo, Sweden Filed: Mar. 22, 1972 Appl. No.: 237,026

Inventor:

Assignee:

Foreign Application Priority Data Mar. 31, 1971 Sweden 4165/71 US. Cl 102/16, 102/19.2, l02/70.2,

102/83 Int. Cl. F42b 15/10 Field of Search 102/76, 77, 78, 79,

[56] References Cited UNITED STATES PATENTS 3,010,395 11/1961 Maltby lO2/l9.2 X 3,000,315 9/1961 Anastasia et al 102/78 Primary ExaminerSamue1 W. Engle Att0rneyLaurence R. Brown [57] ABSTRACT An underwater arming device responsive to water pressure comprises a rotating body including a printed circuit for electrically actuating a detonator after a predetermined degree of rotation. A latch prevents rotation until water pressure exceeds a predetermined value. Rotation speed is controlled by a set of discs engaging a viscous medium.

5 Claims, 4 Drawing Figures 1 ARMING DEVICE FOR A SUBMERSIBLE EXPLOSIVE WEAPON This invention relates to an arming device for a submersible explosive weapon, comprising a housing in which a detonator is mounted movable between a first position in which the main explosive charge of the weapon is impossible upon ignition of the detonator and a second position in which such ignition is possible, a locking mechanism preventing movements from said first to said second position, a releasing device actuated by pressure of the surrounding medium to release the locking mechanism when a certain pressure limit is exceeded, motor means for imparting speed controlled movement of the detonator from said first position to said second position upon releasing of the locking device.

Launching of mines, torpedos etc calls for use of an arming device which is safe against premature detonation, but will arm the weapon in a reliable way a predetermined time after the launching. Such weapons are provided with a number of different types of sensors which when activated will cause'ignition of the explosive charge. The object of the present invention is to provide an arming device which may perform a number of activities regarding safety precautions and arming at a time sequence which may be kept within narrow limits even after a long storage period.

According to the present invention this is obtained thereby that said detonator is mounted in a detonator holder rotatably mounted in said housing the said motor means being designed as a spring urging to rotate the detonator holder relative the housing against the action ofa viscous brake, said locking mechanism comprising a latch mounted in the housing and said releasing device including a piston mounted in a cylinder and adapted to contact and move a latch when a certain pressure upon said piston is obtained.

The invention will be described in more detail reference being made to the drawing in which FIG. 1 is a side view of an arming device according to the invention,

FIG. 2 is a section along the line IIII of FIG. 1,

FIG. 3 is a section along the line IlI--lIl of FIG. 2 and FIG. 4 is a side view of a detail of the device.

Referring to FIGS. 1-3, the reference numeral 1 designates a cylindrical protecting wall having a cover 2. Inside the wall 1 a housing is mounted stationary. Said housing comprises a protective ring 3 and two end covers 4, 5 rigidly connected thereto. The ring 3 is lined with a fire depressing material such as foam rubber 6. Two identical electric detonators 7 and 8 are mounted in a detonator holder 9 pivotally mounted in the cover 4 and in a sleeve bearing 10 secured against rotation relative the cover 5 by an arm 11. A spirally wound spring 12 is secured to the sleeve bearing 10 at its inner end and to the detonator holder 9 at its outer end.

A number of axially stacked discs 13 are secured alternatively to the detonator holder and to the cover 4. The axial. distance between adjacent surfaces of the discs 13 is rather small and the spaces between said discs are filled with silicon oil of high viscosity.

A latch 14 is pivotally mounted at 15 in the ring 3 and prevents rotation of the detonator holder 9 in the direction as shown by an aroow in FIG. 3. The latch 14 may be released by a releasing device comprising a piston 16 axially movable in the cover 2.

The piston 16 is covered by a membrane 17 and is urged upwardly by a compression spring 18 resting against a shoulder surface in the cover 2. The piston 16 carries a piston rod 19 the upper end of which is secured against axial movements by a locking pin 20. The lower end of the piston rod 19 is adapted to contact the latch 14 to turn said latch in counter-clockwise direction.

The detonator holder 9 carries a printed program disc 21 and the cover 5 carries a number of contact elements 22-24 engaging said disc as shown in FIG. 2. These details are shown separately in FIG. 4 in a side view. FIG. 4 shows also two further contact elements 25 and 26.

The printed program disc 21 is made of insulating material on which three areas 27, 28, 29 of electrically conducting material are printed.

The device described will operate as follows:

Prior to launching the arming device the pin 20 is removed. After launching the device into the sea the water will act upon the membrane 17 and cause the piston 16 to move downwards as soon as the water pressure is sufficient to overcome the force of the compression spring 18. The downward movement of the piston rod 19 will move the latch 14 in the counter-clockwise direction and release the detonator holder which will start rotating in the direction indicated by the arrows in FIGS. 3 and 4. The rotation is caused by the spirally shaped spring 12. The speed of rotation is controlled by viscous friction offered by the discs 13 moving relative each other in a film of silicon oil.

As will be seen in FIG. 4 the two printed areas 28 and 29 are initially short circuited by the contact member 26. The said areas are connected in parallel with the ignition coils of the electric detonators 7, 8. Thus, the detonators are secured against premature ignition caused by induction currents in the ignition system.

The electric power supply feeding any electronic cir cuits incorporated in the ignition system of the weapon is not activated until the program disc 21 has been turned so far in the direction of the arrow that the contact element 22 has reached the area 27 through which it now is connected with the contact element 25, the said two elements being coupled in series in a main power source (not shown).

The contact elements 23 and 24 are output terminals of the ignition system of the weapon. It will be understood that the detonators become coupled into said ignition system shortly after the short-circuiting of the ignition coils of the detonators has ceased i.e. after the program disc has been turned about After of travel of the program disc 21 the movement of the detonator holder is stopped. The detonators 7, 8 are now in positions in which detonation will cause a flame directed downwardly through an opening 30 in a cover 31 resting on the ignition charge indicated by the reference numeral 32 in FIG. 3.

As will be seen in FIG. 3 the detonator holder 9 is provided with a number of cavities 33 along the surface part thereof passing the latch 14 during the rotation of the detonator holder 9. Thus, in case the weapon is recaptured shortly after being launched the spring 18 may cause the piston rod 19 to move upwards while a spring 34 urges the latch into contact with the detonator holder 9. The latch 14 may now engage one of the cavities 33' and stop further movement of the detonator holder 9.

I claim:

1. An arming device for a submersible explosive weapon comprising in combination, a housing, an explosive in said housing, an electrically ignitable detonator for said explosive, spring motor means rotatively moving said detonator in said housing from a first position in which the detonator cannot fire the explosive charge toward a second position in which the detonator can fire the explosive charge, a locking mechanism preventing movement of said detonator toward said second position comprising a latch in said housing releasably engaging said rotatable detonator to prevent rotation thereof, a movable piston comprising a releasing device responsive to a predetermined pressure of a medium surrounding said housing to release said locking mechanism, a brake controlling the rotation speed of said motor means including a set of electrical contacts stationary in said housing, and a program disc with an electric circuit thereon relatively rotated by said motor with said detonator to actuate said contacts, said electric circuit and said contacts presenting patterns for short circuiting the detonator for preventing ignition for a predetermined arc of rotation of said detonator, and for electrically activating said detonator after a further predetermined arc of rotation of said detonator wherein said detonator has a plurality oflatch elements engageable with said latch in said housing at different angularly displaced positions of rotation of said detonator.

2. An arming device according to claim 1, wherein said detonator has a plurality of latch elements engageable with said latch in said housing at different angularly displaced positions of rotation of said detonator.

3. An arming device for a submersible explosive weapon comprising in combination, a housing, an explosive in said housing, an electrically ignitable detonator for said explosive, spring motor means rotatively moving said detonator in said housing from a first position in which the detonator cannot fire the explosive charge toward a second position in which the detonator can fire the explosive charge, a locking mechanism preventing movement of said detonator toward said second position comprising a latch in said housing releasably engaging said rotatable detonator to prevent rotation thereof, a movable piston comprising a releasing device responsive to a predetermined pressure of a medium surrounding said housing to release said locking mechanism, and a viscous brake controlling the rotation speed of said motor means wherein said viscous brake comprises closely spaced friction surfaces respectively located on said detonator and said housing with the spaces between said surfaces filled with silicon oil of high viscosity.

4. An arming device as defined in claim 3 wherein said means moving said detonator from the first to the second position comprises a set of electrical contacts stationary in said housing, and a program disc with an electric circuit thereon relatively rotated by said motor with said detonator to actuate said contacts, said electric circuit and said contacts presenting patterns for short circuiting the detonator for preventing ignition for a predetermined arc of rotation of said detonator, and for electrically activating said detonator after a further predetermined arc of rotation of said detonator.

5. An arming device according to claim 4, having electric activating equipment and an electric supply, characterized in that the program disc (21) on the detonator holder (9) in cooperation with the contact elements (22-26) in the housing (3-5) is arranged to successively a. connect said supply of electric power to the electronic activating equipment,

b. remove said short-circuiting of the detonator, and

c. to connect together the detonator and the activating equipment. 

1. An arming device for a submersible explosive weapon comprising in combination, a housing, an explosive in said housing, an electrically ignitable detonator for said explosive, spring motor means rotatively moving said detonator in said housing from a first position in which the detonator cannot fire the explosive charge toward a second position in which the deTonator can fire the explosive charge, a locking mechanism preventing movement of said detonator toward said second position comprising a latch in said housing releasably engaging said rotatable detonator to prevent rotation thereof, a movable piston comprising a releasing device responsive to a predetermined pressure of a medium surrounding said housing to release said locking mechanism, a brake controlling the rotation speed of said motor means including a set of electrical contacts stationary in said housing, and a program disc with an electric circuit thereon relatively rotated by said motor with said detonator to actuate said contacts, said electric circuit and said contacts presenting patterns for short circuiting the detonator for preventing ignition for a predetermined arc of rotation of said detonator, and for electrically activating said detonator after a further predetermined arc of rotation of said detonator wherein said detonator has a plurality of latch elements engageable with said latch in said housing at different angularly displaced positions of rotation of said detonator.
 2. An arming device according to claim 1, wherein said detonator has a plurality of latch elements engageable with said latch in said housing at different angularly displaced positions of rotation of said detonator.
 3. An arming device for a submersible explosive weapon comprising in combination, a housing, an explosive in said housing, an electrically ignitable detonator for said explosive, spring motor means rotatively moving said detonator in said housing from a first position in which the detonator cannot fire the explosive charge toward a second position in which the detonator can fire the explosive charge, a locking mechanism preventing movement of said detonator toward said second position comprising a latch in said housing releasably engaging said rotatable detonator to prevent rotation thereof, a movable piston comprising a releasing device responsive to a predetermined pressure of a medium surrounding said housing to release said locking mechanism, and a viscous brake controlling the rotation speed of said motor means wherein said viscous brake comprises closely spaced friction surfaces respectively located on said detonator and said housing with the spaces between said surfaces filled with silicon oil of high viscosity.
 4. An arming device as defined in claim 3 wherein said means moving said detonator from the first to the second position comprises a set of electrical contacts stationary in said housing, and a program disc with an electric circuit thereon relatively rotated by said motor with said detonator to actuate said contacts, said electric circuit and said contacts presenting patterns for short circuiting the detonator for preventing ignition for a predetermined arc of rotation of said detonator, and for electrically activating said detonator after a further predetermined arc of rotation of said detonator.
 5. An arming device according to claim 4, having electric activating equipment and an electric supply, characterized in that the program disc (21) on the detonator holder (9) in cooperation with the contact elements (22-26) in the housing (3-5) is arranged to successively a. connect said supply of electric power to the electronic activating equipment, b. remove said short-circuiting of the detonator, and c. to connect together the detonator and the activating equipment. 